同塔三回输电线路耐雷性能研究

在珠三角地区，为缓解输电线路走廊紧缺与电力输送能力不足之间的矛盾，建设了大量的同塔三回输电线路。与普通的同塔双回线路相比，同塔三回线路的杆塔更高，更容易引雷。介绍了反击和绕击耐雷性能的计算方法，在此基础上，以广东地区某500kV同塔三回线路为例进行了计算分析。计算结果表明：对于500kV及以上输电线路，工作电压会对反击和绕击性能产生影响；同塔三回线路的杆塔较高，可根据各层横担高度不同进行差异化绝缘配置；同时，当考虑多层导线间相互屏蔽效应后，处于不同层的导线绕击跳闸率均减小；导线的绕击跳闸率不仅随地面倾角的减小而减小，还随保护角的减小而减小。

Lightning Performance of Triple-Circuit Power Transmission Lines

In order to alleviate the contradiction between power transmission corridors and power transmission capacity in Peral River Delta Area, a number of triple-circuit power transmission lines have been built. Compared with normal double- circuit transmission line, the tower of triple-circuit transmission line is much higher so that it is more likely to be struck by lightning. This paper introduces the calculation method of lightning performance of shielding failure and back flashover by settling a 500 kV triple-circuit transmission lines in Guangdong as an example. The result shows that for 500 kV and above transmission lines, the operating voltage will affect the lightning performance of shielding failure and back flashover. Due to the higher tower of triple-circuit transmission line, the insulation configuration can be different according to the height of cross arm in each layer. When considering the mutual shielding effect of lines, shielding failure rates of all lines at different layers will all decrease. In addition, the shielding failure rates will decrease with the decrease of shielding angles and fielding angles.